Figures

Fig. 1Temporal trends in secularization versus economic development over the 20th century, for four illustrative countries.

Each panel represents a country’s secularization score S derived from the WEVS on the y axis, for birth cohorts by decade t on the x axis. The trends are independently determined from each of five different survey periods, p, corresponding to five waves of the WEVS: p1, 1990–1994; p2, 1995–1999; p3, 2000–2004; p4, 2005–2009; p5, 2010–2014.

Fig. 2Time series of secularization versus GDP per capita, from four illustrative countries, over the 20th century.

Each red line represents the mean secularization score, St, of the birth cohort in decade, t, for that country. Each blue line represents the mean GDP per capita (normalized to 1990 US$) during decade t in that country.

Fig. 3Emergence of the correlation between secularization and development during the 20th century.

The top left panel shows scatter plots for secularization, St, against log GDPt per capita (normalized to 1990 US$), for people born in 1910 and 1990, where each point is a country. The top right panel shows R2 values for GDPt versus St, for the decades of the 20th century, t. The bottom left panel shows the same scatter-country plot for St against Vt for people born in the 1910s and the 1990s. The bottom left panel shows the progression of this correlation through the decades of the 20th century.

The time lag is y = 2 decades in all cases (results for y = 1, 2, and 3 decades in table S14). SEs, in parentheses, were determined from the inverse of the negative Hessian matrix (44). N is the number of data points for each autoregression, n is the number of countries included in the data set, i is the percentage of residual variance explained by the random effect (country), and h is the percentage explained by cultural heritage. R2 is the total variance explained. Bonferroni-corrected significance: *P < 0.1, **P < 0.05, ****P < 0.01.